Boris I of Bulgaria

Boris I of Bulgaria (825-2 May 907) was the king of Bulgaria from 852 to 889, succeeding Presian of Bulgaria and preceding Vladimir of Bulgaria.

Biography
Boris was born in 825, the son of Presian of Bulgaria. Boris succeeded his father as King of the First Bulgarian Empire upon his death in 852, and when Boris took the throne, he began the Christianization of Bulgaria. He abolished Tengrism, and he also secured the ability to have a Bulgarian Church loyal to Orthodox Christianity. However, his reign was also full of military setbacks, and his campaign against East Francia in alliance with Great Moravia failed and Ludwig II of East Francia invaded Bulgaria in revenge. Also, the Byzantine Empire seized Philippopolis (Plovdiv) and the ports on the Gulf of Burgas in the Black Sea, and the Principality of Serbia defeated him in 854. In 885 he brought in Saints Cyril and Methodius after they were banished from Great Moravia, and by the end of his reign, Bulgaria had become a large Christian empire. When he died in 907, he was succeeded by Vladimir of Bulgaria.